[Health effects of nanomaterials on next generation]

In order to discuss the health effects of nanomaterials, we cannot disregard the research on the health effects of airborne particulates. It is said that many of the fine or ultrafine particles in airborne particulates originate from diesel vehicles in metropolitan areas. The results of not only animal experiments but many epidemiologic surveys and volunteer intervention experiments in humans are reported on the health effects of particles. Although the health effects of the particulate matter particle sizes below 10 µm (PM10) were investigated in the initial studies, recently even smaller particles have come to be regarded as questionable and research of the health effects of the minute particulate matter below 2.5 µm (PM2.5) has been done. However, our recent study about maternal exposure to diesel exhaust suggests that health effect study of PM0.1, particles below 0.1 µm (100 nm), namely nanoparticles, is necessary from now on. We are proceeding with the study of the health effects of various types of intentionally produced nanomaterials such as carbon black, carbon nanotube, fullerene and titanium dioxide, examining in particular their influence on next generation. Although there are differences in the sites affected and the seriousness of the damage, basically similar findings to DEPs mentioned above are being discovered in research on nanomaterials. Regardless of dosage and administration method, such as inhalation, endotracheal administration, nasal drip and subcutaneous administration, once nanomaterials enter the bloodstream of a pregnant mother mouse, they move to the offspring and have effects on them. The effects may appear as various symptoms in the process of growth after birth, and can sometimes lead to the onset and aggravation of serious diseases.